Handheld controller



FIG. 1 is a perspective view of a handheld controller incorporating the new design;

FIG. 2 is a front view thereof;

FIG. 3 is a back view thereof;

FIG. 4 is a right side view thereof, the left side view being a mirror image of the right side view;

FIG. 5 is a top view thereof; and,

FIG. 6 is a bottom view thereof, wherein the broken lines form no part of the claimed design. 

I claim the ornamental design for a handheld controller, as shown and described. 